On Mon 16-04-18 14:06:21, Vlastimil Babka wrote: > On 04/16/2018 01:41 PM, Michal Hocko wrote: > > On Fri 13-04-18 10:37:16, Johannes Weiner wrote: > >> On Fri, Apr 13, 2018 at 04:28:21PM +0200, Michal Hocko wrote: > >>> On Fri 13-04-18 16:20:00, Vlastimil Babka wrote: > >>>> We would need kmalloc-reclaimable-X variants. It could be worth it, > >>>> especially if we find more similar usages. I suspect they would be more > >>>> useful than the existing dma-kmalloc-X :) > >>> > >>> I am still not sure why __GFP_RECLAIMABLE cannot be made work as > >>> expected and account slab pages as SLAB_RECLAIMABLE > >> > >> Can you outline how this would work without separate caches? > > > > I thought that the cache would only maintain two sets of slab pages > > depending on the allocation reuquests. I am pretty sure there will be > > other details to iron out and > > For example the percpu (and other) array caches... > > > maybe it will turn out that such a large > > portion of the chache would need to duplicate the state that a > > completely new cache would be more reasonable. > > I'm afraid that's the case, yes. > > > Is this worth exploring > > at least? I mean something like this should help with the fragmentation > > already AFAIU. Accounting would be just free on top. > > Yep. It could be also CONFIG_urable so smaller systems don't need to > deal with the memory overhead of this. > > So do we put it on LSF/MM agenda? If you volunteer to lead the discussion, then I do not have any objections. -- Michal Hocko SUSE Labs
